An experimental treatment targeting a form of acute myeloid leukemia has been designated a breakthrough therapy by the Food and Drug Administration, according to the drug’s manufacturer.

Midostaurin (Novartis) is an oral drug used alongside standard chemotherapy for adults with newly-diagnosed AML who are positive for the FMS-like tyrosine 3 (FLT-3) mutation and can undergo chemotherapy. AML has the lowest survival rate of all leukemias, and about one-third of AML patients have the FLT-3 mutation.

The FDA’s breakthrough therapy designation, in place since 2012, is an intensive form of fast-tracking in which the agency offers the manufacturer more guidance on an efficient drug development program and a higher level of organizational support, though future approval is not guaranteed. To qualify, a therapy must come with preliminary clinical evidence demonstrating substantial improvement on at least one clinically significant endpoint over available therapy, according to the agency.

Results from a phase III clinical trial , presented in December 2015 at the 57th annual meeting of the American Society of Hematology, showed that among 717 patients randomized to receive midostaurin alongside standard induction and consolidation chemotherapy or the same chemotherapy protocol alone, the midostaurin group saw significant improvement in overall survival (hazard ratio, 0.77, P = .0074).

Mean OS for patients in the midostaurin arm was 74.7 months (95% CI: 31.7, not attained), compared with 25.6 months for the placebo arm (18.6, 42.9). Median follow-up in the study was 57 months for surviving patients.

In a news release Feb. 19, Novartis said that midostaurin would be submitted for FDA approval for FLT-3-positive AML and that the company had launched compassionate use and expanded access programs allowing newly diagnosed patients aged 18 and older to receive midostaurin alongside standard induction and consolidation therapy. No targeted AML treatments are currently approved by FDA.

FLT3 is a receptor tyrosine kinase that plays a role in the proliferation in the number of certain blood cells. Midostaurin is a multi-targeted kinase inhibitor that is also being investigated for the treatment of aggressive systemic mast cell leukemia, according to Novartis.